Swedish psychologist K. Anders Ericsson has studied elite performers in music, chess and sport for decades, and he says the main distinguishing characteristic of experts is the amount of deliberate practice they’ve invested – typically over 10,000 hours.

This is painstaking practice performed for the sole purpose of improving one’s skill level. Best-selling authors like Gladwell, Daniel Pink, Matthew Syed and others, have taken Ericsson’s results and distilled them into the uplifting message that genius is grounded almost entirely in hard work.

But now a team led by David Hambrick have published a forceful challenge to the 10,000 myth. “We found that deliberate practice does not account for all, nearly all, or even most variance in [elite music or chess] performance,” they write.

The researchers looked for studies into chess players that provided information on people’s highest ability level achieved and their past history of practice. They found six studies supplying this information, published between 2005 and 2012, and involving collectively over 1000 players from around the world.

On average, amount of deliberate practice accounted for 34 per cent of variance in chess ability – an impressive proportion, but by no means sufficient to explain why some players achieved greatness while others didn’t. Even more revealing was the huge range of deliberate practice completed by players of different standards. Focusing only on the grandmasters from one study, the range of practice they’d invested was 832 to 24,284 hours. Looking at players who achieved only intermediate level, 13 per cent of them had actually completed more practice than the average amount invested by the grandmasters.

Hambrick’s team performed a similar analysis with past studies involving hundreds of elite musicians – mostly pianists. Based on eight past papers, they found deliberate practice accounted for 30 per cent of the variance in music performance, as measured by formal tests, expert ratings and rankings. Again there was evidence of wide variation in the the amount of practice completed by different musicians. The take-out was clear – some people failed to achieve the highest level even after completing substantially more than 10,000 of practice; others achieved the highest level with only relatively modest practice.

“The bottom line,” write Hambrick and his colleagues, “is that deliberate practice is necessary to account for why some people become experts in these domains and others fail to do so, but not even close to sufficient.” What else matters? Another relevant factor, they say, is starting age. This correlates with amount of completed practice, but crucially, it remains a predictive factor even after subtracting the influence of practice. “This … suggests that there may be a critical period for acquiring complex skills,” the researchers said.

Other relevant factors include intelligence, and working memory capacity (the latter is also correlated with elite performance level even after subtracting the role of practice completed); personality; and genes.

Let’s briefly revisit two of the popular science authors who have spread the 10,000 hour myth:

“Ten thousand hours is the magic number for greatness,” wrote Gladwell.

“[There was] nobody who had reached the elite group without copious practice, and nobody who had worked their socks off but failed to excel,” wrote Syed.

Hambrick and his team say these claims are simply “incorrect”. Their findings suggest that “some normally functioning people may never acquire expert performance in certain domains, regardless of the amount of deliberate practice they accumulate.” This may sound disheartening, but there is a “silver lining”. People can avoid wasting time on futile dreams, say Hambrick et al, and “gravitate towards domains in which they have a realistic chance of becoming an expert through deliberate practice.”

Pinker yesterday tweeted about “another refutation of the Gladwellian claim that the effects of practice prove that talent doesn't matter,” in that case referring to a new study showing that fast sprinters were already very fast even when they were young, and didn't “become” fast by practicing so hard: http://goo.gl/mXmZc2

The only “myth” here is the one that was started by the people who read too much into what Gladwell said. 1st string violinists have 10k hours of practice under their belt only because they had enough talent to make investing that kind of effort worth it. The “out” group had less than 10k because they had the sense to quit wasting their time practicing to become something they could never be.

I never took Gladwell to mean that practice could MAKE you something you're not… I'm surprised that people read so much into it.

If there were really a chess grandmaster who had only practiced for 832 hours, as the article claims, that would be an amazing refutation of the 10,000 rule.

But the claim doesn't stack up

For a start the 832 hours was to reach “Master” level, not “Grandmaster” – a completely different chess level. (based on Hambrick, 2014, “Deliberate practice: Is that all it takes to become an expert?”)

Although “master level” is not an extremely high level (there are tens of thousands of players meeting that standard), achieving it in 832 hours is still an amazing achievement. Even world champions like reigning World Chess Champion Magnus Carlsen took longer than two years of playing to reach that standard. So who is this amazing player? Presumably the scientists have lots of convincing data to back this up?

Well, er, no, actually, they don't. They actually gathered the data for their study by leaving a questionnaire in the lobby of a chess club in Buenos Aires. So some guy in Buenos Aires filled in this anonymous survey and filled in “Master” for his level and wrote that he had been seriously studying chess for 832 hours. There is no evidence whatsoever to confirm that the evidence is reliable. For all we know, the person filling in the questionnaire might have been fooling around, or lying, or misunderstood the question. I have to say I find it much more likely that the questionnaire was filled in by someone fooling around and having a joke, rather than having been filled in by an amazing undiscovered chess genius who achieved master status faster that the most renowned chess champions in history.

This is why I still believe the 10,000 hours rule is a good rule of thumb for how long it takes to get world class at something like chess. There are lots of claims of people doing it faster, but on closer inspection, they are not convincing.